Important Comparisons in Networking

COMPARISON BETWEEN ADSL AND SDSL

ADSL	SDSL
Asymmetric DSL	Symmetric DSL
Provides asymmetric communication	Provides symmetric communication
Provides higher speed in the downstream direction than in the upstream direction	Provides full-duplex asymmetric communication supporting upto 768 kbps in each direction

COMPARISON BETWEEN CIRCUIT SWITCHING, PACKET SWITCHING AND MESSAGE SWITCHING

Circuit Switching	Packet Switching	Message Switching
There is physical connection between transmitter and receiver.	No physical path is established between transmitter and receiver.	No physical path is set in advance between transmitter and receiver.
All the packet uses same path.	Packet travels independently.	Packets are stored and forward.
Needs an end to end path before the data transmission.	No needs of end to end path before data transmission.	Same as packet switching.

COMPARISON BETWEEN TCP AND UDP

TCP	UDP
Transmission Control Protocol	User Datagram Protocol
Connection oriented	Connectionless
Reliable	Unreliable
Ordered	Unordered
Slow	Fast
Heavyweight	Lightweight
Streaming	Datagrams
Packet is called segment	Packet is called user datagram
Connection is byte stream	Connection is message stream
Inclusion of checksum is mandatory	Inclusion of checksum is optional
Provides error control, flow control and congestion control	Does not provide flow control, error control and congestion control
Supports full duplex transmission	Does not support full duplex transmission
Retransmission of lost packets is possible	Retransmission of lost packets is not possible
Takes less interaction between the sender and receiver	Takes more interaction between the sender and receiver
Does not support multicasting and broadcasting	Support multicasting and broadcasting
Applications: www, e-mail, remote administration, file transfer	Applications: DNS, streaming media, online games